<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>变量的作用域练习题</title>
</head>
<body>
<script>
    function fl(a) {
        alert("a" + a);
        a = 2;
        alert("b" + a);
        alert("c" + a);
    }
    var a = 1;
    fl(a);
    alert("cc" + a);
    alert("bb" + a);
</script>

</body>
</html>